This invention relates to a recording medium cartridge of the type which includes a memory for storing information concerning signals recorded on the recording medium, and more particularly is related to a manner of storing information in the memory of such a recording medium cartridge so as to promote higher efficiency in the management and retrieval of the information stored in the memory and of the signals recorded on the recording medium.
In a known type of recording medium cartridge, such as a magnetic tape cassette, information concerning the magnetic tape, such as the thickness, the type, the length, the grade, etc., of the magnetic tape, can be determined on the basis of a plurality of detection holes (hereinafter referred to as “recognition holes”) that are provided at a corner of the rear face of the cassette.
However, as the size of cartridges has been reduced, it has become increasingly difficult both to provide locations for the recognition holes and to provide a desired amount of information using the number of recognition holes which are available.
Moreover, in order to determine what materials are recorded on the magnetic tape, it is necessary to advance or rewind the magnetic tape to reach the position on the tape at which the material of interest is recorded. This often requires a significant period of time.
To overcome these problems, it has been proposed to include in a recording medium cartridge a memory, separate from the magnetic tape, for storing information with respect to the cartridge and the materials recorded on the tape. Such a recording medium cartridge is disclosed, for example, in U.S. Pat. Nos. 4,338,644 and 4,383,285.
With a recording medium cartridge of the type just described, having a memory for storing information concerning the materials recorded on the recording medium, it is important that the information stored in the memory accurately reflect the materials recorded on the recording medium and also that the information stored in the memory be managed efficiently. However, the prior art fails to disclose any system for managing the information stored in the memory.